docs: def fromstring(text, schema=None):
      """Parses a KML text string
      
      This function parses a KML text string and optionally validates it against 
      a provided schema object"""
      if schema:
          parser = objectify.makeparser(schema = schema.schema)
          return objectify.fromstring(text, parser=parser)
      else:
          return objectify.fromstring(text)